STATE OF IDAHO MAR I 2

DEPARTMEI'..JT OF 

ENVIRONMENTAL QUALITY 

GfFICE m: tHE EXECUlIYE 

1410 North Hilton· Boise, Idaho 83706 • (208) 373-0502 C.L. "Butch" Otter, Governor 

Toni Hardesty, Director 

March 9, 2009 

Michelle Pirzadeh, 

Acting Regional Administrator 

USEP A, Region 10 


1200 Sixth Avenue, Suite 900 


Seattle, WA 98101 

Dear Ms. Pirzadeh: 

On behalf of the Governor of the State of Idaho and as the director of the Idaho 

Department of Envirorunental Quality (DEQ), I am submitting to you Idaho's 

recommendations for area designations for the 2008 revised eight-hour ozone National 

Ambient Air Quality Standard (NAAQS). 

Section 1 07( d)(1) of the Clean Air Act defines an area as nonattairunent if it is violating 

the NAAQS or contributing to a violation in a nearby area. Core Based Statistical Area 

(CBSA) or Combined Statistical Areas (which includes two or more CBSA's) associated 

with violating monitor(s) serve as the starting point or "presumptive" boundary for the 

geographic extent of a nonattairunent area. For rural areas the presumption is that the 

designation will be made for the entire county in which the monitor is located. 

Three complete calendar years of Federal Reference Method (FRM) ozone data have 

been evaluated for three monitors in the state ofIdaho (Table 1). Per CFR requirements, 

DEQ operates two monitors in the Treasure Valley (Boise City-Nampa metropolitan 

statistical area (MSA)) and one monitor in the Coeur d' Alene MSA in north Idaho, 

Idaho's ozone monitoring network is designed to assess population exposure to the 

highest expected ambient concentrations in populated areas. Data collected from these 

monitors indicate attairunent of the eight-hour ozone NAAQS; therefore, Idaho is 

recommending attairunentlunclassifiable designations for these areas: 
• 	 Boise City-Nampa MSA, including: 


-Ada County 


-Boise County 


-Canyon County 


-Gem County 


-Owyhee County 


• 	 Coeur d' Alene, ID Metropolitan Statistical Area: 


-Kootenai County 


The rest of the state should be designated as attainmentlunclassifiable for the eight-hour 

ozone NAAQS since no monitoring is taking place. 

2008 monitoring data has not been certified and is not final. DEQ is working with 

Region 10 to address certain "missing days" for its Whitney Elementary School monitor 

in Boise. DEQ is confident that this monitor will meet all Appendix P data completeness 

requirements once the demonstration is made to Region 10 and concurrence is accepted. 

The missing days will then be appropriately coded in AQS, and DEQ will complete the 

data certification process. A similar situation exists for the Lancaster monitor in north 

Idaho. In both cases, the three-year aggregate data completeness falls one percentage 

point short of the required ninety percent. All data must be certified by July 1,2009. 

In the future, should it be necessary to redesignate an area as "nonattainment," we intend 

to evaluate the appropriate EPA guidance and any other relevant considerations to 

determine presumptive boundaries for that area, rather than default to CBSA or county 

boundaries. 

If EPA has any further questions or concerns, please coordinate through Martin Bauer, 

DEQ, Air Quality Division Administrator (208/ 373-0552). 

Sincerely, ",' 

((O~~ 

Toni Hardesty 

Director 

c: 	 Governor Butch Otter 

Bonnie Butler, Office of the Governor 

Martin Bauer, DEQ 

Bruce Louks, DEQ 
Table 1. 2006- 2008 Ozone Monitoring Summary, Idaho Department of Environmental Quality 

Year Site Airs ID 1st max 

8-hour 

ave 

ppm 

2nd max 

8-hour 

ave 

ppm 

3rd max 

8-hour ave 

ppm 

4th max 

8-hour ave 

ppm 

Data 

Completeness 

% 

2008 Lancaster Rd - Hayden 160550003 0.061 0.06 0.059 0.059 93 

2007 Lancaster Rd - Hayden 160550003 0.072 0.071 0.071 0.067 95 

2006 Lancaster Rd - Hayden 160550003 0.075 0.068 0.068 0.068 78 

3-yr design value 0.064 

3-yr average data 

completeness 89 

2008 ITO - Boise 160010019 0.079 0.075 0.072 0.072 80 

2007 ITO - Boise 160010019 0.082 0.081 0.080 0.080 58 

2006 ITO - Boise 160010019 0.078 0.076 0.074 0.074 84 

3-yr design value 0.075 

3-yr average data 

completeness 74 

2008 Whitney - Boise 160010030 0.077 0.074 0.072 0.069 92 

2007 Whitney - Boise 160010030 0.086 0.085 0.078 0.076 84 

2006 Whitney - Boise 160010030 0.09 0.088 0.083 0.082 88 

3-yr design value 0.075 

3-yr average data 

completeness 

. 89